Across
- 3. An almost colorless fluid present in lymph vessels; similar in composition to blood plasma.
- 7. Red pigment found in red blood cells that reversibly binds to oxygen.
- 8. A patch of muscle in the wall of the right atrium whose rate of contraction is faster than the rest of the cardiac muscle and initiates the contraction of the heart.
- 12. Originating in muscle tissue rather than nerve impulses.
- 15. The sequence of events taking place during one heart beat.
- 16. The smallest type of blood vessel whose function is to facilitate the exchange of substances between blood and tissues.
- 18. Blood vessels that carry blood away from the heart.
- 19. A hollow muscular organ that pumps blood through the circulatory system by rhythmic contraction and dilation.
Down
- 1. Red liquid that circulates in the arteries and veins carrying oxygen to and carbon dioxide away from the tissues of the body.
- 2. Valve with two flaps that lies between the left atrium and the left ventricle.
- 4. Yellowish liquid component of blood that holds blood cells and proteins.
- 5. Blood vessels that carry blood to the heart from other parts of the body.
- 6. Maintaining a relatively constant environment for the cells within the body.
- 8. Circulation from the heart to the lungs and back.
- 9. Circulation from the heart to the rest of the body and then back to the heart.
- 10. Valve with three flaps that lies between the right atrium and the right ventricle.
- 11. The muscle tissue that makes up most of the heart.
- 13. Large veins that carry deoxygenated blood to the heart.
- 14. A partition separating the two chambers of the heart.
- 17. The main artery of the body.